Nun's Well is an ancient underground water reservoir in the British Overseas Territory of Gibraltar. It is located at Europa Point, and is thought to be of the Moorish period. It represents some of the earliest evidence of an artificial water supply in Gibraltar. The name of the cistern is thought to be derived from the nuns associated with the Shrine of Our Lady of Europe. In the eighteenth century, Nun's Well supplied the military with water. In the early nineteenth century, it provided water for the brewery that was built next door. In 1988, the Royal Engineers constructed what is now the main building, which has a castle-like appearance. Nun's Well became the focus of controversy during the 2010-2011 restoration of the site.

Europa Point, is the southernmost point of Gibraltar. Although not the southernmost point of the Iberian Peninsula, Europa Point defines the boundary between the Straits of Gibraltar in the Atlantic Ocean, and the Alboran Sea within the Mediterranean. At the end of the Rock of Gibraltar, the area is flat and occupied by such features as a playing field and a few buildings. On a clear day, views of North Africa can be seen across the Strait of Gibraltar including Ceuta and the Rif Mountains of Morocco; as well as the Bay of Gibraltar and the Spanish towns along its shores. It is reached from the old town by Europa Road.